Electric heater



R. G. LEDIG.

ELECTRIC HEATER.

AFPLicATloN FILED AuG.27, 1921.

Patented May 9, 1922.

lro

UNITEDA STATES" PATENT OFFICE.

i VANTIA.

. RICHARD G. rIIEDIG, OF PHILADELPHIA, PENNSYLVANIA; ASSIGNOR T0 A. MECKY COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A..y CORPORATION OF PENNSYL- ELECTRIC nur.

' Specification of Letters Patent. May 9, 1922 Application led August 27, 1921i Serial No. 495,886.

To allwhomz'tmay coment.'

Be it known that nI, RICHARD G. Lnnro, a citizen of the United States, residing in Philadelphia, Pennsylvania, have lnvented Electric Heaters, of which the following 1s a s ecification. D

ne object of this inventionis to provide a relatively simple, compact and convenlent device for electrically heating or melting liquid or solid materials, which device. shall be compact, ornamental and convenlently portable as well as inexpensive to make and operate. f

These objects and other advantageous ends I attain as hereinafter set forth, reference being had to the accompanying draw.- ings,` in which,

Fig. 1 is a central vertical section of an electric heater constructed in accordance with my invention;

Fig. 2 is a plan of the heater shown in Fig. 1; and

Fig. 3 is a fragmentary vertical section on the line 3 3, Fig. 2.

In the above drawings 1-2 represents a two-partsupporting frame Vof which the first part is a hollow, approximately frustoconical casting. designed to rest upon its basal portion and the second part is likewise a hollow open frusto-conical structure having its basal portion uppermost, being, as shown in Fig. 3, rigidly connected to the portion 1 by Screws 3. Between these two parts of the frame is clamped the flange of a ring 4 and a plate in the form of a disc 5 of refractory non-conducting material centrally recessed for the reception of one end of a hollow cylinder 6 also of `refractory substance, such as porcelain or other earthenware material.

The screws 3 which serve to clamp together theframe members and the bottom plate 5, also engage and hold an` annular plate 7 against the top end of the cup 6 so that the latter is immovably clamped iu place. The plate 7 is at a level somewhat below the plane of the end of the top frame member 2 and is centrally cut away to provide an opening 8 into the cup 6 preferably of the same diameter as the latter. An electrical heating element 9 in the form of a wire winding is mounted upon or embedded toa greater or less extent in the outer surried out to a pair of terminals 10 and 11 in vthereto 'poor conductor of heat,

the form of bolts insulated from a. metal supporting plate 12 whose edges are extended between andk clamped frame member plate 5. n v

' Supply conductors 13 and 14 are electrically connected to the terminals 10 and 11 whlch are to some extent venclosed and protected by a circular'metal plate 15 fitting into the hollow base structure 1 and held by screws of which one is indicated at 16. The cup formed by the base plate 5 and c linder 6has a bottom opening 17 for the a mission of air and under conditions of use the fiow of current through the heating element 9 heats the walls of said cup to a high degree.' Any structure mounted on the relatively flat top end of the frame member 2 or inserted within the cup is thus heated by the hot air rising, from and around said cup and this air is deflected or spread over the bottom of a structure on the frame member 2 by the annular plate 7 whose outer edge is spaced away from the inner walls of said member 2 so that the air is free to pass l ald the refractory base upwardly around it as well as through its 'and 2 have vertically elongated openings formedin their walls so that there is a free flow of air to and around the heating element which at the same time serves to keep said frame members themselvesat a relatively vlow temperature. It isto be noted that the vbase plate 5 extends outwardly beyond the heatingelement and vthe cylinder 6 on vwhich it is mounted, so that it' is engaged by the metallic elements 1 and 4 at some distance therefrom. Since said base plate is a relatively this prevents objectionable conduction of heat from the cylinder 6 to the frame and insures the high heating of the air in the immediate vicinity of the cup and its heating element as well as of the deflector plate 7 I claim:

1. The combination in an electric heater of a frame including two hollow frustoconical members; means for holding said members with their small diameter ends together; a refractory structure fixed within said frame; and a heating element wound on said structure.

carried by but .electrically in position by the upper end ofv thel of the heating cup 2. Thecombination of a hollow frame; a hollow' c linder of refractory material mounted 1n said frame with its axis substantially vertical; d and a heating element `wound on said cylinder.

two frusto-conical members; a base plate mounted between the smaller ends of said members; a heating element mounted on said base plate and extending upwardly there- .from within one of the frame members, said element including a winding; with terminals for said winding within the interior of the second frame member.

6. The combination of an open work fra-me; a cup of refractory material mounted on said frame; and a heating winding for said cup.

' 7. The combination of an open work frame; a refractory cup rigidly held within sald frame with its opening adjacent the open top end of said frame; and a heating element Wound on the cu i.

RICHA D G. LEDIG. 

